Means for heating metals.



E. F. GEHRKBNS. MEANS FOR HEATING METALS.

APPLICATION FILED JULIE, 190B. v

Patented Sept 20,1910.

2 BHEETE-BHEET 1- WITNEEIEIEEII INVENTDRI EDWARDEBEHRKEN:

ATTY.

UNITED STATES PTENT OFFICE.

EDWARD F. GEHR KENS, 01? SCHENECTADY, NEW YORK, ASSIGNOB '10 GENERAL ELEC- 'IBIC COMPANY, A CORPORATION OF YORK.

means FOR nnnrme METALS.

Specification of Letters Patent.

Patented Sept. 20, 1910.

Application filed July 6, 1908. Serial No. 442,150.

To all whom it may concern:

Be it known that I, EDWARD F. Gnn ucnns, a citizen of the United States, residing at Schenectady, county of Schenectady, State of New York,'have invented certain new and useful Improvements in Means for Heating Metals, of which the following is a specification.

My invention relates to means for heating metal, and is articulai'lyapplicable to the heating of rai s, car wheels and the like, a portion or portions of which it is desired to temper or harden.

According to my invention, I heat the metal rail or the like by generating'current in a portion or portions of the metal by .means of an electrical transformer, this portion or portions being in inductive relation to the primary of the transformer, another portion of the rail being in the magnetic circuit of the transformer.

In another aspect, my invention comprises the combination with a magnetic core having a winding thereon, of apiece of metal to be heated, a portion ofwhich being in the magnetic circuit of said core, and another portion or portions placed in inductive relation to said winding.

Other featuresof my invention are pointed out with particularity in the claims annexed to and forming a part. of this specification. For a better understanding of my invention however, reference may be had to the following description taken in con ncction with the accompanying drawing, in

. Figure 1- is a perspective view of a rail and a magnetic core arranged in accordance -with my invention; Fig. '2 is a' section on the line 22 of Fig.3 looking in the direction of the arrows, and Fig. 3 is aview of a magneticfcore and car wheel with parts broken away and in section, arranged in accordance with my invention;

Referring .to Fi ..1 of the drawing, the tread portion 3 0 the rail 4 is heated by current induced in it by the changing flux in the ma netic core 5, This core 5 is laminated an towhich alternating current is sup lied from a suitable source by means of the eads .7. This coil of wire 6 acts as the primary of a transformer. The laminations of the core 5'do not form a complete magneticciris wound with a coil of wire 6' duced in'the rail at-so'me one instance flows in one direction through the tread portion 3, the portion 10 the web 9 and flange 9 in parallel, and the portion 11 of the rail, and the next instance in the opposite direction in these portions. Since the tread portion 3, which is in inductive relation to the winding 6 and the core 5', is of small cross-section,

as compared with the combined cr0sssection of the web and flange, the current density will be much greater in the tread portion and it will become heated whilethe web and -flange will remain comparatively cool.

When it reaches the proper degree of heat, the core '5 is removed and the rail tempered, or any other operation performed that is desired. i

By placing the core sothat the tread ortion and the web and flange portion, w ich are in inductive relation to the winding and core, are of equal cross-section, the whole rail may be equally heated, the portion which is in the magnetic circuit of the core being of relatively small cross-section and heated by edd currents and by conduction. By making tli whole section of-rail may be heated.

Referring to Figs. 2 and 3, the portion or portions 12 comprisin the rim-of the car wheel 13 are placed n inductive relation to the coils 14 of the magnetic core 15. This core 15 isbuilt up of laminations of involute cross-section closely pac'kedto form a.hollow c linder, as disclosed in the application of alter 0, Fish, No. 351,968, filed January 12, 1907, for ma etic cores for electric apparatus. The 001 s 14 are laced in recesses in the core. The core is divided at 16 and has a gap at 17, so that itmay be placed about the wheel 13, the portion 18 e core 5 ofgreat length, a

rst inone direction and thenin the other. This heats'it and when it reaches the proper temperature the core is removed and the rimtem-' pered, or 0 rated upon as desired.

What I aim as new and desire to secure by Letters Patent of the United States, is: 1. In combination, a magnetic core having a winding thereon, and a piece of metal, a ortion of which is in the magnetic circult of said core, and a portion or portions to be heated in inductive relation to said winding.

2. In combination, a'magnetic core having a gap therein, and a winding thereon a piece of ma etic material, a portion of which is in sai gap and completes the magnetic circuit of said core, and a portion or portions in inductive relation to I said winding. V

3. In combinatiom a'magnetic core hava ing a winding thereon, and a piece of metal, a portion of which is in the magnetic circuit of said core, and another portion or ,fits in said gap, an

portions which, form a link about the magnetic circuit of said core.

4. In combination, a magnetic core having a gap therein, a winding on said core, and apiece of metal a portion of which d another portion or portions which forms a link about the magnetic circuit of said core. a

5. In combination, a magnetic core having a p therein, a winding on said core, and a 'sk-shaped giece of magnetic metal, a portion of which ts' in said ga and, completes the magnetic circuit of sai core, and another portion or portions which forms a link about the magnetic circuit of said core. In witness whereof, I have hereunto setmy hand this 3rd day of July, 1908.-

EDWARD F. GEHRKENS.

Witnesses: I v

HELEN Oaronn,

BENJAMIN 

